U.S. patent application number 10/500889 was filed with the patent office on 2005-03-03 for alkylglycol alkoxylates or alkyldiglycol alkoxylates, mixtures thereof with tensides and their use.
Invention is credited to Gumbel, Helmut, Kroner, Hubertus, Lichterfeld-Weber, Nicole, Noerenberg, Ralf, Oetter, Gunter, Seelmann-Eggebert, Hans-Peter, Tropsch, Jurgen.
Application Number | 20050049167 10/500889 |
Document ID | / |
Family ID | 26010943 |
Filed Date | 2005-03-03 |
United States Patent
Application |
20050049167 |
Kind Code |
A1 |
Noerenberg, Ralf ; et
al. |
March 3, 2005 |
Alkylglycol alkoxylates or alkyldiglycol alkoxylates, mixtures
thereof with tensides and their use
Abstract
The invention relates to alkylglycol alkoxylates and
alkyldiglycol alkoxylates that are obtainable by alkoxylating
C.sub.4-8 alkylglycols or diglycols with C.sub.2-5 alkoxides up to
an average alkoxylation degree of 1 to 8, based on the
C.sub.4-8alkylglycols or diglycols. The invention further relates
to mixtures from C.sub.2-5 alkoxylates of C.sub.4-8 alkylgycols or
-diglycols that have an average alkoxylation degree of 1 to 8 and
tensides that have an interfacial tension of less than 45 mN/m at
20.degree. C. when dissolved in an amount of 5 g/l of water, and/or
to diyhdroxyalkins or derivatives thereof.
Inventors: |
Noerenberg, Ralf;
(Ingelheim, DE) ; Oetter, Gunter; (Frankenthal,
DE) ; Tropsch, Jurgen; (Romerberg, DE) ;
Gumbel, Helmut; (Dannenfels, DE) ; Lichterfeld-Weber,
Nicole; (Romerberg, DE) ; Kroner, Hubertus;
(Neustadt, DE) ; Seelmann-Eggebert, Hans-Peter;
(Limburgerhof, DE) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Family ID: |
26010943 |
Appl. No.: |
10/500889 |
Filed: |
July 7, 2004 |
PCT Filed: |
January 21, 2003 |
PCT NO: |
PCT/EP03/00551 |
Current U.S.
Class: |
510/421 |
Current CPC
Class: |
C11D 1/72 20130101; B01F
17/0085 20130101; B01F 17/0092 20130101; B01F 17/0028 20130101;
C11D 7/263 20130101; B01F 17/0021 20130101 |
Class at
Publication: |
510/421 |
International
Class: |
C11D 017/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 21, 2002 |
DE |
102 02 007.8 |
Sep 30, 2002 |
DE |
102 45 886.3 |
Claims
1-14. (Cancelled).
15. An alkylglycol alkoxylate or alkyldiglycol alkoxylate that is
free from alcohol obtained by the process comprising: alkoxylating
C.sub.4-8-alkylglycols or -diglycols with C.sub.2-5-alkoxides to an
average degree of alkoxylation of from 1 to 8, based on the
C.sub.4-8-alkylglycols or -diglycols.
16. A mixture of C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols
-or diglycols which, on average, have a degree of alkoxylation of
from 1 to 8 as claimed in claim 15, and surfactants which,
dissolved in an amount of 5 g/l of water, exhibit an interfacial
tension of less than 45 mN/m at 20.degree. C., and/or
dihydroxyalkynes or derivatives thereof.
17. A mixture as claimed in claim 16, wherein the surfactants are
nonionic surfactants and are chosen from C.sub.2-5-alkoxylates of
C.sub.9-20-alkanols which, on average, have a degree of
alkoxylation of from 3 to 30, and mixtures thereof.
18. A mixture as claimed in claim 16, wherein the surfactants are
low-foam or foam-suppressing surfactants.
19. A laundry detergent, cleaner or wetting agent or cosmetic,
pharmaceutical or crop protection formulation comprising a mixture
as claimed in claim 16.
20. A mixture as claimed in claim 16, comprising 0.1 to 20% by
weight of the C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols or
-diglycols, based on the total weight of the mixture or of the
composition.
21. A method of reducing the interfacial tension and accelerating
the establishment of the interfacial tension in aqueous surfactant
formulations or aqueous dispersions comprising: contacting the
aqueous surfactant formulations or aqueous dispersions with
C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols or -diglycols
which, on average, have a degree of alkoxylation of from 1 to 8, as
claimed in claim 15.
22. A method of lowering the viscosity of surfactant-containing
formulations comprising: contacting these surfactant-containing
formulations with C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols
or -diglycols which, on average, have a degree of alkoxylation of
from 1 to 8, as claimed in claim 15.
23. A laundry detergent, cleaner or wetting agent or cosmetic,
pharmaceutical or crop protection formulation comprising a mixture
as claimed in claim 17.
24. A laundry detergent, cleaner or wetting agent or cosmetic,
pharmaceutical or crop protection formulation comprising a mixture
as claimed in claim 18.
25. A laundry detergent, cleaner or wetting agent or cosmetic,
pharmaceutical or crop protection formulation comprising
alkylglycol alkoxylates or alkyldiglycol alkoxylates as claimed in
claim 15.
26. A mixture as claimed in claim 17 comprising 0.1 to 20% by
weight of the C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols or
-diglycols, based on the total weight of the mixture.
27. A mixture as claimed in claim 18 comprising 0.1 to 20% by
weight of the C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols or
-diglycols, based on the total weight of the mixture.
28. A laundry detergent, cleaner or wetting agent or cosmetic,
pharmaceutical or crop protection formulation as claimed in claim
19, comprising 0.1 to 20% by weight of the C.sub.2-5-alkoxylates of
C.sub.4-8-alkylglycols or -diglycols, based on the total weight of
the composition.
Description
[0001] The present invention relates to alkylglycol alkoxylates or
alkyldiglycol alkoxylates, mixtures of alkylglycol alkoxylates or
alkyldiglycol alkoxylates with each other and with surfactants, to
compositions and formulations comprising these and to the use of
such alkylglycol alkoxylates or alkyldiglycol alkoxylates in
aqueous formulations or spray applications, preferably in
surfactant-containing formulations which can also comprise
dispersions or emulsions, e.g. coating compositions, cosmetic
formulations and agrochemical formulations.
[0002] The rapid wetting of surfaces plays a central role in many
areas of daily life and in many industrial processes, for example
during the cleaning or coating of substrates. In many formulations,
therefore, varying amounts of alcohol such as ethanol or
isopropanol are used in order, for example, to lower the surface
tension and thus to improve the wetting ability of the
formulations. In this connection, it is customary to add often
relatively large amounts of these alcohols to aqueous formulations.
However, the physiological effect of the alcohols is unacceptable,
and exposure for the user to such formulations is high as a result
of the high vapor pressure of the alcohols. In addition, the
properties of the alcohol as solvent especially in the case of
plastic-containing surfaces lead to sometimes irreparable surface
damage by partially dissolving the surfaces. Longer-chain alcohols,
such as octyl alcohol or decyl alcohol, cannot completely overcome
the physiological problems associated with their use either. For
this reason, only small amounts of alcohols or no alcohol should
nowadays be present, for example, in surfactant formulations which
are handled directly by the user. However, for very rapidly wetting
formulations, such as humectants in the printing industry or
additives for coating formulations, for example for paper finishing
by a paper coating, they continue to be a necessary
constituent.
[0003] For some years the very good wetting action of very
hydrophobic, compact alcohols, which can be prepared from acetylene
and aldehydes, has been known. These are, in particular,
dihydroxyalkynes. However, these products are not compatible with
all cleaner formulations and can often only be used using
solubilizers such as cumene sulfonate. In this connection, it is
often necessary to use a relatively large amount of the solubilizer
compared with the wetting auxiliary, resulting in high secondary
costs due to the use of the dihydroxyalkynes. In addition, the
effect of the wetting auxiliary is impaired upon mixing with
relatively large amounts of solubilizers.
[0004] A customary method of increasing the wetting rate of aqueous
formulations consists in using surfactants which position
themselves on interfaces and thus lower the interfacial tension.
While, by adding alcohols such as ethanol or isopropanol to aqueous
formulations, the resulting water/solvent mixture has a lower
surface tension compared to water and thus exhibits improved
wetting behavior, the wetting or surface coating in the case of the
use of surfactant systems is dependent on time. The surfactant
molecules must firstly diffuse at the surface and form an
interfacial film there, as a result of which the interfacial
tension or the surface tension in the case of the contacting of
water and air decreases. In the case of very rapid processes, such
as, for example, spraying or wetting processes, for example
fountain solutions in the printing industry, the time in which the
surface or interfacial tension is reduced to the equilibrium value
by the surfactant system is decisive. The dynamics of the
surfactant system is of great importance here for the wetting
rate.
[0005] One application according to the invention is described, for
example, by reference to a spray coating process. Such a spray
coating process can, for example, be used in the production of
coated paper with a dispersion.
[0006] In spray coating, the coating composition is atomized using
pressure in a special nozzle to give fine droplets and sprayed onto
the base paper. This mainly results in a uniform drop formation.
The smaller the drops, generally the more uniform the applied layer
since coverage of the surface with drops is more compact for a
given coating weight. Between application and the subsequent drying
step, the applied layer of drops should also level and even
out.
[0007] Thus, spray coating and curtain coating mainly results in
low surface tensions of the coating compositions. At the same time,
the coating compositions should foam only slightly or not at all
and have a minimal air content. Since paper finishing is a rapid
production process (in practice coating speeds of up to 2000 m/min
are achieved, newer pilot plants even permit speeds in excess of
3000 m/min), particular requirements are placed on the dynamic
behavior of the coating compositions.
[0008] Other applications of a spraying process are found in the
production of aerosols in medicinal or technical sectors or in
painting in the domestic and commercial sector or in the
application of crop protection formulations.
[0009] The coating of the interface by surfactant molecules takes
place partially by free molecules (monomers) and by the breaking of
aggregates and subsequent adsorption, meaning the exchange rate of
the surfactant between solution and micelle is decisive. It is
known that solubilizers such as cumene sulfonate impair aggregation
of the surfactant in solution and therefore reduce solubility. As a
result, hydrophobic wetting agents can be formulated at increased
concentrations. However, the effect of the wetting agent in the
formulation, which in most cases is used in dilute form, is reduced
as a result. The solubilizers are in themselves not active at the
interface. However, there are also amphiphilic structures, referred
to as solubilizers, which solubilize hydrophobic molecules in the
form of micelles. Interaction with the surfactants is nonspecific
and indirect. For this reason, solubilizers do not enter directly
into the process of interface coating either.
[0010] Low molecular weight alcohols with low degrees of
ethoxylation, such as butyl diglycol and hexyl glycol, are known as
nonaqueous solvents and are used in conjunction with surfactants in
formulations. However, like the alcohols, these compounds are not
physiologically acceptable, and their performance is not comparable
with the performance of the dihydroxyalkynes or alcohols.
[0011] In addition, alcohol ethoxylates of lower alcohols are
currently used as suitable wetting agents. However, as a result of
the preparation, such products often contain amounts of alcohol,
which again contribute decisively to the rapid wetting and, in
cases of very short wetting times, may be the sole wetting
component.
[0012] WO 95/27034 describes, for example, detergent compositions
in the form of an oil-in-water microemulsion. They comprise a
short-chain ethoxylated nonionic surfactant which has a short alkyl
chain length. The ethoxylated nonionic surfactants are obtained by
ethoxylation of short-chain alcohols. The specification is one
example of publications which describe alcohol ethoxylates.
[0013] The use of ethoxylated alkanols in cleaners is also
described in EP-A 0 620 270. The cleaner compositions described
therein, however, do not comprise surfactants, but one polar
solvent and one nonpolar or weakly polar solvent. The alkylene
glycol alkyl ethers used therein should have an affinity both for
the polar solvent and also for the nonpolar solvent and thus serve
as solubility promoters.
[0014] The use of alkoxylates of shorter-chain alcohols as low-foam
wetting agents is also described in EP-A 0 681 865. They are used
here in combination with propylene oxide-modified shorter-chain
alkanols. They can be used, in particular, in textile
precursors.
[0015] U.S. Pat. No. 5,340,495 describes compositions which can be
used for removing printing ink in printing machines. The cleaning
liquids comprise, for example, a main fraction of a soybean oil
methyl ester and smaller amounts of ethoxylated hexanol. The
ethoxylated C.sub.4-10-alcohols, described in general form, which
contain 2 to 10 mol of ethylene oxide per mole of alcohol, are
described as solubility promoters and removers of printing ink.
[0016] It is an object of the present invention to improve the
wetting behavior of known wetting agents or laundry detergents or
cleaners. In such compositions, the aim is to reduce the
interfacial tension and also to accelerate the establishment of the
interfacial tension. The disadvantages of the known additives for
laundry detergent, cleaners and wetting agents are to be avoided.
The dynamics of known surfactant systems are to be improved or be
achieved using toxicologically acceptable ingredients. In addition,
the aim, for example in formulations such as paper coating
dispersions for spray coating, is to reduce the particle size and
the foaming, and to improve the printability of the resulting
papers. In addition, the aim was to optimize the formulations in
spray applications such that the particle size and the foaming are
reduced. Examples thereof are paper coating compositions, paints,
surface coatings, cleaners or cosmetic or medicinal sprays.
[0017] We have found that this object is achieved according to the
invention by alkylglycol alkoxylates or alkyldiglycol alkoxylates
obtainable by alkoxylation of C.sub.4-8-alkylglycols or -diglycols
with C.sub.2-5-alkoxylates to an average degree of alkoxylation of
from 1 to 8, based on the C.sub.4-8-alkylglycols or -diglycols.
[0018] We have found that this object is also achieved according to
the invention by the use of C.sub.2-5-alkoxylates of
C.sub.4-8-alkylglycols or -diglycols which, on average, have a
degree of alkoxylation of from 1 to 8, for reducing the interfacial
tension, in particular in short times of, customarily, less than 1
second, and accelerating the establishment of the interfacial
tension in aqueous surfactant formulations or aqueous
dispersions.
[0019] We have found that this object is also achieved by the use
of the C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols or
-diglycols which, on average, have a degree of alkoxylation of from
1 to 8, as solubilizers which, in particular, do not have any
negative effect, but a positive effect on the wetting ability of
wetting auxiliaries even in dilute systems, and for increasing the
solubility of wetting auxiliaries in aqueous formulations which
comprise nonionic surfactants.
[0020] We have also found that C.sub.2-5-alkoxylates of
C.sub.4-8-alkylglycols or -diglycols which, on average, have a
degree of alkoxylation of from 1 to 8 can be used for lowering the
viscosity of surfactant-containing formulations.
[0021] We have found that this object is also achieved by the use
of C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols or -diglycols
which, on average, have a degree of alkoxylation of from 1 to 8 for
increasing the wetting rate in aqueous wetting agents.
[0022] We have found that this object is also achieved by the use
of C.sub.2-5-alkoxylates of C.sub.4-8-alkylglycols or -diglycols
which, on average, have a degree of alkoxylation of from 1 to 8 for
reducing the particle size in formulations for spray
applications.
[0023] According to the invention, it has been found that a
synergistic effect arises when surfactants are used together with
the alkoxylates according to the invention, in particular
ethoxylates of lower alkylglycols or -diglycols, which ensures that
the interfacial tension between the aqueous solution and air is
reduced to the value of, for example, alcohol-containing
formulations within a few fractions of a second. By combining the
lower alkylglycol alkoxylates or alkyldiglycol alkoxylates which
have a very weak interface affinity according to the invention with
surfactants it is possible both to reduce the level of interfacial
tension, and also to considerably increase the rate at which the
level is reached.
[0024] This synergistic effect arises particularly in the case of
mixtures of C.sub.2-5-alkoxylates, preferably of
C.sub.2-4-alkoxylates of C.sub.4-8-alkylglycols or -diglycols
which, on average, have a degree of alkoxylation of from 1 to 8,
and surfactants which, dissolved in an amount of 5 .mu.l of water,
exhibit an interfacial tension of less than 45 mN/m at 20.degree.
C. and/or dihydroxyalkynes or derivatives thereof. The invention
thus also relates to these mixtures.
[0025] The mixtures according to the invention can thus replace a
large number of known formulations, for example alcohol-containing
formulations.
[0026] The statements below refer just as much to alkyldiglycols as
to alkylglycols or alkoxylates thereof.
[0027] The mixtures according to the invention comprise, as one
component, C.sub.2-5-alkoxylates, i.e. alkoxylates with
C.sub.2-5-alkoxides, of C.sub.4-8-alkylglycols which, on average,
have a degree of alkoxylation of from 1 to 8. The alkylglycols may
be linear or branched alkylglycols. The binding of the
C.sub.4-8-alkyl radical to the glycol may be terminal or at any
other position along the alkyl chain. Preference is given to linear
alkylglycols, in particular to linear, terminal alkylglycols. The
alkyl radicals of the alkylglycols preferably have 4 to 6 carbon
atoms. The degree of alkoxylation is, on average, 1 to 8,
preferably 2 to 6. For the alkoxylation, preference is given to
using C.sub.2-4-alkoxides. Preference is given to using ethylene
oxide, propylene oxide, butylene oxide or mixtures thereof.
Particular preference is given to using ethylene oxide. The
preferred ranges are also based on the alkylglycol alkoxylates and
alkyldiglycol alkoxylates per se.
[0028] The preparation takes place starting from alcohol-free,
preferably pure alkylglycols and alkyldiglycols and not, as
otherwise customary, starting from alkanols, by alkoxylation. The
product mixtures therefore do not comprise any residual alkanols,
but at most alkylglycols. A distribution of the alkoxylation degree
specific for alkylglycols results. As a result of the preparation
process, the alkylglycol alkoxylates are free from alcohols.
[0029] Alkoxylates are oligomeric or polymeric reaction products
with alkoxides. Because of the kinetics of polymerizations known to
the person skilled in the art, a random distribution of homologs
automatically results, the average value for which is usually
quoted. The frequency distribution of the homologs includes the
starting material particularly at low degrees of alkoxylation.
Although the choice of catalyst can influence the distribution to a
certain extent, nothing changes with regard to the principle of the
distribution curve. Pure alkyloligoglycols can be prepared only by
distillative or chromatographic processing and are therefore
expensive. Furthermore, it has been found that the distribution of
the homologues has a considerable influence on the aggregation
behavior.
[0030] The alkoxylates described here have the homolog distribution
important for the aggregation behavior and the other properties
according to the invention, without containing alcohol.
[0031] The distribution of the degrees of alkoxylation can be
determined by chromatographic processes.
[0032] The table below shows the distribution curves for a
customary n-hexanol ethoxylate (+3 EO), derived from n-hexanol, and
an n-hexylglycol ethoxylate (+2 EO), derived from n-hexylglycol,
side by side. The first column gives the amount of ethylene oxide
(0-6) bonded to the n-hexyl radical (C6). On average, the two
compounds contain the same amount of EO units.
1 Area % Chemistry n-Hexanol + 3 EO n-Hexylglycol + 2 EO C6 E00 2.4
0 C6 E01 5 8.3 C6 E02 10.2 20.3 C6 E03 13.5 24.6 C6 E04 14.3 19.4
C6 E05 13.5 12.9 C6 E06 11.2 7.5 Remainder 29.9 7
[0033] The samples were prepared using KOH as catalyst by
introducing 2 or 3 mol/(mol of starting material) of ethylene oxide
into the starting material in question. Analysis is carried out by
gel permeation chromatography (GPC) in THF. The hexanol signal was
identified by spiking with hexanol, and the higher homologues from
the sequence of the other signals. Evaluation was carried out by
integration of the signal areas.
[0034] Since no alcohols are present in the product mixture
according to the invention, it is substantially odor free.
Surfactants which can be used according to the invention are all
surfactants which, dissolved in an amount of 5 g/l of water,
exhibit an interfacial tension of less than 45 mN/m at 20.degree.
C. The surfactants are generally alkoxylated alcohols, amides,
acids, betaines, amine oxides or amine, but also dihydroxyalkynes
and derivatives and mixtures thereof. The rate of the establishment
of the ultimate level of the interfacial tension may depend here on
the molecular architecture, such as the chain length and the degree
of branching of the alcohol, the length and solvation of the
alkoxylate, the surfactant concentration and surfactant
aggregation. Generally, smaller aggregates diffuse more rapidly
than large aggregates.
[0035] The surfactants are preferably nonionic surfactants and
chosen from C.sub.2-5-alkoxylates, preferably
C.sub.2-4-alkoxylates, of C.sub.9-20-alkanols, preferably
C.sub.9-15-alkanols, in particular C.sub.9-20-alkanols which, on
average, have a degree of alkoxylation of from 3 to 30, preferably
4-15, in particular 5 to 12, and mixtures thereof. In particular,
C.sub.9-11-alkanols are used to construct the surfactants. In this
connection, the alkanols may be linear or branched. In the case of
a branched alcohol, the degree of branching is preferably in the
range from 1.1 to 1.5. The alkoxylation can be carried out with any
desired C.sub.2-4-alkoxides and mixtures thereof. Alkoxylation can
be carried out, for example, with ethylene oxide, propylene oxide
or butylene oxide. Particular preference is given to using ethylene
oxide, propylene oxide or mixtures thereof. Particular preference
is given to ethylene oxide. The degree of alkoxylation is, on
average, 3 to 8, preferably 3 to 6. Such nonionic surfactants are
known and are described, for example, in EP-A 0 616 026 and EP-A 0
616 028. These specifications also mention shorter-chain alkyl
alkoxylates.
[0036] The nonionic surfactants used as surfactants may also be
replaced by dihydroxyalkynes or derivatives thereof. These may also
be low-foam or foam-suppressing surfactants, cf. also EP-A 0 681
865 and the literature cited at the beginning. Low-foam and
foam-suppressing surfactants are known to the person skilled in the
art.
[0037] In the mixtures according to the invention, the alkylglycol
alkoxylates are preferably used in an amount of from 0.05 or 0.1 to
20%, preferably 0.1 to 10% by weight, particularly preferably 0.5
to 7% by weight, especially 0.8 to 5% by weight, based on the total
weight of the mixture. The remaining proportion of the mixtures is
allotted to the surfactants. These amounts are also valid for the
laundry detergents, cleaners, wetting agents, care compositions,
crop protection compositions and cosmetic compositions or other
compositions prepared from the mixtures or alkylglycol
alkoxylates.
[0038] Laundry detergents or cleaners which may comprise a
combination of the surfactants with alkanol alkoxylates are
described, for example, in WO 01/32820. The compositions described
therein additionally comprise solid particles with a particle size
of from 5 to 500 nm. Such particles are usually not present in the
mixtures according to the invention. The glycol ethers described in
the WO application are described therein as hydrophilizing agents.
The mixtures according to the invention can have the further
ingredients described in WO 01/32820.
[0039] The present invention also relates to laundry detergents,
cleaners or wetting agents which comprise a mixture or alkylglycol
alkoxylate as described above. In addition, the invention relates
to surface coatings, adhesives, leather-treatment compositions or
textile-treatment compositions which comprise a mixture or
alkylglycol alkoxylate or alkyldiglycol alkoxylates as described
above. The mixtures according to the invention can be used with a
formulation of compositions in all areas in which highly dynamic
formulations are used. Examples thereof are
[0040] all-purpose cleaners, textile detergents, spray cleaners,
hand dishwashing detergents for cleaning in the private, industrial
and institutional sector including metal working,
[0041] humectants, printing roll and printing plate cleaners in the
printing industry,
[0042] cosmetic, pharmaceutical and crop protection
formulations,
[0043] paints, ink formulations, coating compositions, e.g. for
paper, adhesives in the paints and polymer film industry,
[0044] formulations for spray applications, for example, in ink
jets, paints, medicaments or cosmetics,
[0045] leather treatment, such as leather degreasing and leather
greasing,
[0046] metal treatment, such as anticorrosion formulations,
cutting, grinding or boring auxiliaries and lubricants,
[0047] formulations in the textile industry, such as leveling
agents or formulations for yarn cleaning.
[0048] flotation auxiliaries and foaming auxiliaries.
[0049] Such formulations usually comprise further ingredients, such
as surfactants, builders, fragrances and dyes, complexing agents,
polymers and other ingredients. Typical formulations are described,
for example, in WO 01/32820. Further ingredients suitable for
different applications are described, by way of example, in EP-A 0
620 270, WO 95/27034, EP-A 0 681 865, EP-A 0 616 026, EP-A 0 616
028, DE-A 42 37 178 and U.S. Pat. No. 5,340,495.
[0050] In general, the mixtures according to the invention can be
used in all sectors in which the action of interface-active
substances is required.
[0051] Like the classical solubilizers, the ethoxylated lower
alkylglycols used according to the invention increase the
solubility, in particular of nonionic surfactants, and thus
simultaneously provide for a clear solution of hydrophobic
surfactants. Although a lowering of the interfacial tension of the
solubilizers alone is also observed, this proved to be much lower
than the effect of surfactants and alcohols.
[0052] As a result of the use of non-surface-active structures, the
formulations according to the invention have better environmental
and skin compatibility compared with systems described, for
example, in EP-A 0 616 026. In contrast to common solubilizers,
such as cumene sulfonates, interaction takes place specifically
with the surfactants. The alkoxylated alkylglycols used according
to the invention thus actively penetrate into the coating of the
interface and accelerate the establishment of the interfacial
equilibrium.
[0053] According to the invention, it is not necessary and not
desired for a residual content of alcohol to be present in the
mixtures or formulations according to the invention. According to
one embodiment, the mixtures, compositions and formulations
according to the invention are free from alcohol and preferably
also from alkylglycols or diglycols, in particular from
C.sub.4-8-alkylglycols and C.sub.9-13-alkanols. According to the
invention it has been found that surfactant formulations with high
interface dynamics can be formulated using the alkylglycol
alkoxylates according to the invention without a residual content
of alcohol which is usually present in lower alcohol alkoxylates in
the product as a consequence of the preparation.
[0054] The wetting action according to the invention can be
determined by a dynamic measurement of the interfacial tension, for
example using a bubble pressure tensiometer. A suitable procedure
is described, for example, in S. S. Dukhen, G. Kretzschmar, R.
Miller (Ed.), Dynamics of adsorption at liquid interfaces,
Elsevier, 1995. The wetting action on surfaces can be determined
here by a dynamic measurement of the interfacial tension. Such a
method is the video-aided, time-resolved contact angle
measurement.
[0055] The invention further provides for the use of the alkyglycol
alkoxylates, alkyldiglycol alkoxylates and mixtures thereof in
surface finishing, e.g. paper finishing. The invention thus
provides a coating composition which is an aqueous paper coating
dispersion which comprises water, pigments, binders and 0.05 to 5%
by weight, based on the pigments, of alkyglycol alkoxylates
according to the invention or mixtures thereof. The formulations
can comprise natural or synthetic binders or mixtures thereof.
Further possible ingredients are rheology auxiliaries, dispersants,
thickeners, etc.
[0056] In the coating compositions, the particle size can now be
significantly influenced in the spray coating process, coupled with
simultaneously low lack of foam of the coating compositions and
good printability.
[0057] The pigments used in the coating compositions usually
represent the main component. It is possible to use all customarily
used pigments, such as calcium carbonates, kaolin, tallow, titanium
dioxide, gypsum, chalk or synthetic pigments alone or in a
mixture.
[0058] In addition, the coating compositions can comprise customary
dispersants. Suitable dispersants are polyanions, for example, of
oligo- or polyphosphoric acids or oligo or polyacrylic acids, which
are usually used in amounts of from 0.01 to 3% by weight, based on
the pigment used.
[0059] Suitable coating compositions usually comprise natural
and/or synthetic binders, such as starch, polymer dispersions, such
as, for example styrene/acrylate copolymers or
styrene/acrylate/vinyl acetate copolymers (e.g. Acronale.RTM. from
BASF AG) and/or styrene/butadiene copolymers (e.g. Styronal.RTM.
from BASF AG) and/or tailored polymers which also contain other
ethylenically unsaturated carbon compounds (e.g. Basonal.RTM.),
which generally have a glass transition temperature of from
-20.degree. C. to +50.degree. C.
[0060] The synthetic binders are preferably used in the form of an
aqueous dispersion with a solids content of from 30 to 70%.
[0061] Further constituents of the coating compositions may be
customary additives, such as cobinders, thickeners, such as, for
example, modified starch, casein, polyvinyl alcohol,
carboxymethylcellulose, synthetic thickeners based on acrylate
and/or hardening agents, processing auxiliaries such as Ca stearate
and/or neutralizing agents and/or optical brighteners. These
additives are usually used alone or in a mixture in the coating
composition in amounts of from 0 to 10% by weight, based on the
pigment.
[0062] The alkylglycol alkoxylate or mixture is usually used in
amounts of from 0.05 to 5%, based on the formulation, preferably in
amounts of from 0.1 to 2%. In this connection, the alkylglycol
alkoxylate or mixture can be added either during the preparation
process of the coating composition directly (and/or) or else in a
mixture with a constituent to the coating composition (e.g. a
pigment slurry and/or a binder).
[0063] For the coating of paper surfaces, for example by means of
spray coating, a coating composition is sprayed in the examples
below using the process described in the Wochenblatt fur
Papierfabrikation, (2001), Special Issue "OptiSpray"--Coating and
Sizing Conference Mar. 15, 2001 (published by the Deutscher
Fachverlag GmbH, Frankfurt/Main).
[0064] The droplet sizes formed here can be measured using suitable
analytical methods. This is preferably carried out in a test
apparatus with only one spray nozzle. A suitable analytical method
for determining droplet size distribution is the Fraunhofer
diffraction.
[0065] The invention will be illustrated in more detail below by
reference to examples:
EXAMPLE 1
[0066] An aqueous solution of 2 g/l of a
C.sub.13-C.sub.15-oxoalcohol ethoxylate with an average degree of
ethoxylation of 7 (Lutensol.RTM. A07 from BASF AG) is analyzed
using a bubble pressure tensiometer (model MPT 2 from Lauda). At
equilibrium the interfacial tension is 42 mN/m, which is achieved
after 0.7 s.
[0067] The addition of 1 g/l of cumene sulfonate influences neither
the position nor the dynamics of the surfactant solution.
[0068] The addition of 1 .mu.l of hexylglycol ethoxylate with an
average degree of ethoxylation of 4 shifts the equilibrium value to
39 mN/m. The equilibrium value is achieved after just 0.4 s.
[0069] On the other hand, in a mixture of 1 g/l of the lauryl
alcohol ethoxylate with an average degree of ethoxylation of 7 and
1 g/l of the hexylglycol ethoxylate in equilibrium, an interfacial
tension of 42 mN/m is measured, which was reached after 0.7 s. The
use of hexylglycol ethoxylate thus means that the amount of
surfactant can be considerably reduced.
EXAMPLE 2
[0070] A dihydroxyalkyne (Surfynol.RTM. 104H from Air Products) was
analyzed in a typical fountain solution formulation in the printing
industry. The fountain solution formulation comprises 150 g/l of
glycerol, 770 g/l of water, 20 g/l of sodium dihydrogenphosphate,
40 g/l of succinic acid, 10 g/l of Surfynol 104H. In order to make
the cloudy solution clear, 40 .mu.l of cumene sulfonate
(formulation A) or 20 g/l of hexylglycol ethoxylate with a degree
of ethoxylation of 4 (formulation B) were added. The formulation
was then diluted in the ratio 1:50, so that ultimately the content
of dihydroxyalkyne was 0.2 g/l. The dynamic interfacial tension was
measured using the bubble pressure tensiometer.
[0071] For the formulation A in equilibrium, an interfacial tension
level of 50 mN/m is measured, which is reached after 0.5 s. For
formulation B in equilibrium, a level of 43 mN/m is found, which is
reached after 0.2 s.
[0072] From this it is clear that the formulation B according to
the invention has advantages over comparative formulation A both in
its static and also its dynamic properties.
[0073] Paper Finishing (Spray Coating)
[0074] Paper was coated in accordance with the process given above
using the dispersions given in table 1.
[0075] The particle size during the coating was determined by
Fraunhofer diffraction.
[0076] The particle distributions described in the table were
achieved using an instrument from Malvern with a He--Ne laser,
which represents a laser source with a wavelength of 633 nm. To
record the measurement signals, use was made of a detector array
with 31 elements, which can detect particle sizes from 6 to 560
.mu.m. The evaluation software for the instrument gives, in
addition to the particle size distribution, a characteristic mean
value D50. Table 1 gives the measured mean value of the particle
size distribution of the various formulations.
[0077] Papers which were coated with the coating compositions were
smoothed at room temperature by pressing them through a calender
four times. The nip pressure was 250 kN/m. The papers were then
printed in a single color using a Prufbau print test instrument,
and the printing uniformity was determined using a "Tobias Tester".
This test method is described by Philipp E. Tobias et al in Tappi
Journal Vol. 72, No. 5 (1989). The lower the Mottle Index values,
the more uniform the printing image.
2TABLE 1 Parts of binder Parts of (solid per 100 HE per Parts of
parts of 180 parts SC D50 Mottle pigment pigment of pigment [%]
[.mu.m] Index 100 carbonate 12 Binder A -- 52 42 190 100 carbonate
12 Binder A 1.0 52 27 172 100 carbonate 12 Binder B -- 52 43 206
100 carbonate 12 Binder B 1.0 52 29 178 100 carbonate 12 Binder B
-- 55 40 213 100 carbonate 12 Binder B 1.0 55 28 182 100 carbonate
12 Binder B -- 60 38 216 100 carbonate 12 Binder B 1.0 60 27 185
100 carbonate 12 Binder B 0.6 55 30 184 Carbonate: Ca-carbonate
with an average particle size of 800 mm Binder A: Dispersion of
styrene/acrylate copolymers with a glass transition temperature of
25.degree. C. Binder B: Dispersion of a carboxylated
styrene/butadiene copolymer with a glass transition temperature of
25.degree. C. HE: Hexylglycol ethoxylate with a mean degree of
ethoxylation of 4 SC: Solids content
* * * * *